ABSTRACT
Transportation planning in the public sector is based on the philosophy of continuous growth. Pave it and they will come, bringing economie development, discretionary spending and quality of life with them. The basic elements of a national system of interconnected limited access highways were complete by 1970. Since then, in addition to tinkering with road capacity, transportation planners have taken a second look at transit capacity, which had shrunk considerably under the continuous onslaught of roads, bridges and automobiles. Transportation often is deliberately underpriced, at least in the short run. Cheap transportation begets mobility. Mobility is desirable in and of itself. Mobility may further serve to attract economie growth and development. Travel forecasts usually are limited to those travel demands that would have occurred anyway, in the absence of any new or improved transportation infrastructure. The sensitivity of households and firms to changes in transportation system characteristics are rarely addressed explicitly.
